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Process in Sindarin

The built-in Process type has been deprecated. Please use the SDK-based Process type instead.

Migration to SDK

Import the process module from the SDK:

import "sdk/process"

The SDK provides the Process struct with equivalent functionality:

import "sdk/process"

// Run a command
var p: Process = Process.run("pwd")
print(p.stdout())
print($"Exit code: {p.exitCode()}\n")

// Run a command with arguments
var p2: Process = Process.runArgs("ls", {"-la", "/tmp"})
if p2.success() =>
    print(p2.stdout())
else =>
    print(p2.stderr())

SDK Process API

Static Methods

Method Return Description
Process.run(cmd) Process Run command with no arguments
Process.runArgs(cmd, args) Process Run command with arguments

Instance Methods

Method Return Description
exitCode() int Get exit code (0 = success)
stdout() str Get captured standard output
stderr() str Get captured standard error
success() bool Check if exit code is 0
failed() bool Check if exit code is non-zero
notFound() bool Check if command was not found (exit code 127)

Examples

Basic Execution

import "sdk/process"

var p: Process = Process.run("pwd")
print(p.stdout())      // prints current directory
print(p.exitCode())    // 0 on success

Commands with Arguments

import "sdk/process"

var p: Process = Process.runArgs("ls", {"-la", "/tmp"})
print(p.stdout())

Checking Success

import "sdk/process"

var p: Process = Process.runArgs("make", {"build"})

if p.success() =>
    print("Build succeeded\n")
    print(p.stdout())
else =>
    print("Build failed\n")
    print(p.stderr())

Capturing Output

Stdout and stderr are captured independently:

import "sdk/process"

var p: Process = Process.runArgs("sh", {"-c", "echo out; echo err >&2"})

print(p.stdout())    // "out\n"
print(p.stderr())    // "err\n"

Shell Commands

For pipes, redirection, or shell features, use sh -c:

import "sdk/process"

// Using pipes
var p1: Process = Process.runArgs("sh", {"-c", "ls -la | grep .txt"})
print(p1.stdout())

// Multiple commands
var p2: Process = Process.runArgs("sh", {"-c", "cd /tmp && pwd"})
print(p2.stdout())    // "/tmp\n"

Exit Codes

Non-zero exit codes indicate failure:

import "sdk/process"

var p: Process = Process.run("false")

if p.failed() =>
    print($"Command failed with code {p.exitCode()}\n")

Command Not Found

If the command doesn't exist, the exit code is 127:

import "sdk/process"

var p: Process = Process.run("nonexistent-command")

if p.notFound() =>
    print("Command not found\n")
    print(p.stderr())

Exit Code Reference

Code Meaning
0 Success
1-125 Command-specific failure
126 Command found but not executable
127 Command not found
128+ Killed by signal (128 + signal number)

Limitations

The following features are not supported:

  • Streaming I/O - Cannot read/write while process runs
  • stdin input - Cannot pipe data to process stdin
  • Working directory - Use sh -c "cd dir && cmd" instead
  • Environment variables - Use sh -c "VAR=val cmd" instead
  • Timeouts - Use shell timeout command if needed
  • Kill/signal - Cannot terminate running processes
  • Process ID - Cannot get PID of spawned process
  • Async execution - Use threads for parallel execution

See Also